The hunt continues today for a man spotted running from the scene of the murder of a female special constable.

The suspect who wore a hooded top was spotted immediately after the attack on Nisha Patel-Nasri, 29, who bled heavily and died after being stabbed in the leg while off-duty just yards from her home.

Police were also looking at whether there was a link between the murder and an attempted burglary at her home the previous week.

It is believed Mrs Patel-Nasri ventured out in her night clothes just before midnight on Thursday because she heard thieves trying to break into two high-value cars, one a stretched limousine, belonging to her husband, which were parked outside their home.

Her shocked neighbours at Sudbury Avenue, in suburban Wembley, north London, had rushed outside after suddenly hearing her scream.

She was heard to say: "Somebody stabbed me, please call the police" before collapsing on the pavement. A man in a hooded top was seen running into nearby Sylvester Road immediately after the attack.

Residents went to her aid and tried to stop the bleeding, before alerting her husband, Fadi - who had been out for the evening - and calling the police. When officers arrived she was given further emergency first aid and taken to Northwick Park Hospital, where she later died.

Last Saturday night, three black men had tried to break into her house and only fled when she challenged them in the porch. One theory was that one of the three men could have returned to the house.

Detective Superintendent Julian Worker, who is leading the hunt for her killer, said there was "an awful lot of blood at the scene" and that as a result the suspect was likely to be heavily bloodstained.

"They may have come home with bloodstained clothes," he said. "There may be people who have their suspicions. I'm asking them to come forward. This sort of crime is just so atrocious and so horrendous. No loyalty even to a family member or to a friend is worthy of not coming forward."